SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e3e652e47806689e8d3fa7542982569ab2d19cc015428ae1be43e78783134b2e' 
  AND token = 'LJFMBN+jZDr9dFDz32fR/3KHL7PTXvPHv2LMKNGaDvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}